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[23.128.96.37]) by mx.google.com with ESMTPS id b10-20020a170902d50a00b001bf559a7bc6si21189640plg.465.2023.09.28.10.55.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Sep 2023 10:55:59 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=oO+IJ5rh; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 56A9081CC863; Thu, 28 Sep 2023 07:27:11 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232370AbjI1O1H (ORCPT + 99 others); Thu, 28 Sep 2023 10:27:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56988 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232202AbjI1O1D (ORCPT ); Thu, 28 Sep 2023 10:27:03 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4536419D; Thu, 28 Sep 2023 07:27:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=4veK4h8MnCIHD8dLpIFbw5HKoCnVUh6S/Jh0++RlbFc=; b=oO+IJ5rhHVkD2WElUuMm4fRIjN LxKYnzQ6vkvHTJu9mVx10IyIRe/OrH6eFGm8l6VQj7pCNBMWWZFI9+ISu3amj9xG7hmh19ddQAiul UuoW7Bha8+d/CyvyPtrz9+PF7DYgWdMdn9x45gQinOgdA5eOqCCveDCd0nE8kisONdIhZIb689PcB H7FCgQmhtzDXxNDsIkUjmLQdD6EDNGALUthVVrUZkzKL7Lzc86BubaVmZmPihrPevMyOZ1Bzghrdc YhhrWjBtUxF7/WNFcZRUSeBm0S3hwgiLVguKsGYnIFuqNXLtrG9/2WFO14BPWkzqL4v8KY8BgwvfI 0qJo18CQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1qlryH-002yth-2F; Thu, 28 Sep 2023 14:26:29 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id B59B63002E3; Thu, 28 Sep 2023 16:26:28 +0200 (CEST) Date: Thu, 28 Sep 2023 16:26:28 +0200 From: Peter Zijlstra To: Mathieu Desnoyers Cc: David Laight , "linux-kernel@vger.kernel.org" , Thomas Gleixner , "Paul E . McKenney" , Boqun Feng , "H . Peter Anvin" , Paul Turner , "linux-api@vger.kernel.org" , Christian Brauner , Florian Weimer , "carlos@redhat.com" , Peter Oskolkov , Alexander Mikhalitsyn , Chris Kennelly , Ingo Molnar , Darren Hart , Davidlohr Bueso , =?iso-8859-1?Q?Andr=E9?= Almeida , "libc-alpha@sourceware.org" , Steven Rostedt , Jonathan Corbet , Noah Goldstein , Daniel Colascione , "longman@redhat.com" , Florian Weimer Subject: Re: [RFC PATCH v2 1/4] rseq: Add sched_state field to struct rseq Message-ID: <20230928142628.GC27245@noisy.programming.kicks-ass.net> References: <20230529191416.53955-1-mathieu.desnoyers@efficios.com> <20230529191416.53955-2-mathieu.desnoyers@efficios.com> <20230928103926.GI9829@noisy.programming.kicks-ass.net> <34ddb730-8893-19a8-00fe-84c4e281eef1@efficios.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <34ddb730-8893-19a8-00fe-84c4e281eef1@efficios.com> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Thu, 28 Sep 2023 07:27:11 -0700 (PDT) On Thu, Sep 28, 2023 at 09:20:36AM -0400, Mathieu Desnoyers wrote: > Of course things are more complicated with PI-futex, is that what you have > in mind ? PI futex has to go through the kernel, also, they already spin-wait on owner.